JWS system cache (shared!?!)

I was reviewing:
http://java.sun.com/j2se/1.5.0/docs/guide/deployment/deployment-guide/properties.html
and see there is now a documented method for utilizing a shared system cache. I have read that you can accomplish this in JVM 1.4.2 however it is 'undocumented'. The steps for 1.5 do not work for 1.4.2.
Is there a way to implement a shared system cace in 1.4.2 and if so how? I am kind of stuck on 1.4.2 now, and will not be ready to move up until the Spring (customer requirements).
Thanks for any help in advance!

No, not using Java Web Start 1.4.2 (since the system cache was a new feature in javaws 1.5.0)
You can, however, use javaws 1.5.0 and still use the JRE from 1.4.2
/Andy

Similar Messages

Upgrading JWS applications installed in the system cache (enterprise)

Hello,
On request from several customers, I've looked into the best way to install a web start application for all users on a computer. These customers have users sharing computers, and the IT department doesn't want to be inconvenienced with installing applications on every user profile on every computer. The following articles provides a thorough explanation into how this can be done.
http://download.oracle.com/javase/1.5.0/docs/guide/javaws/developersguide/javaws.html
http://download.oracle.com/javase/1.5.0/docs/guide/deployment/deployment-guide/properties.html
By specifying the system deployment.config and deployment.properties files and performing the following installation command as an administrator, the application is made available for all current and new users with shared icons on the desktop and the start menu. This works actually very nicely.
javaws -system -import https://server/app.jnlp
However, I'm running into different problems when trying to upgrade the application. The application uses an online shortcut (but can be run in offline) and the update check is set to background.
If an ordinary (non-administrator) user start the application when a new version is available on the server, web start downloads the new version in the background, but into the user's personal cache! When restarting the application, the old shared version still starts. Web start does not download the new version, presumably because it found the new files in the personal cache.
Another approach I tested was to use offline icons and manually performing a new system installation/import. This downloads the new version into the shared system cache, but leaves all shortcuts invalid. Now the only solution to start the application is to run it from Java Control Panel. It's not even possible to recreate the shortcuts.
I'm wondering if I'm doing anything wrong or if there exists some best practices for enterprise installations that I'm not aware of. I'm suspecting that these problems are due to limitations or bugs with JWS, but I thought to check with the community before reporting it officially to Oracle.
The customers are using client computers with Windows flavours.
I've been testing on Windows 7 64 bit using the 32 bit JRE 1.6.0_u23.
Any suggestions would be really appreciated. If you are handling enterprise installations in altogether different manner, don't hesitate to respond.
Thanks.

Hello,
Were you able to solve your problem?
Actually, I'm planning to install the application for all users in a system and I'm on the investigation process.
In fact, these are my concerns:
- What is going to happen if a user with limited permissions tries to install a javaws application and it has been enable to be installed on system cache?
- Where the deployment files need to be located? In the web server (where jnlp is located)?
- Could system cache installation be performed automatically (when jnlp file is launched) or it would be performed by a system administrator?
If you could share some information on how you installed a javaws application for all users, I would really appreciate it.

1.5 How to globally set the System Cache location

FROM ANOTHER USER ON ANOTHER BOARD:
This one did not get answered completely.
************************* Question:
Hello,
I want to deploy JWS on a client PC with Microsoft XP OS. This client have multiple users. JWS put a file deployment.properties in the directory "documents and setting" for the current user.
How can I create a uniquely file deployment.properties for all users of this client (new and existing profiles) ?
Create a directory "documents and setting/all users/application data/sun/java/deployment/" with the file deployment.properties don't work.
Create a directory "documents and setting/default user/application data/sun/java/deployment/" with the file deployment.properties is working but is not good for the existing users. This is good uniquely for new users.
is there a solution ?
King regards,
funchung
************************* ANSWER:
For windows, the system config file is at:
{Windows Directory}\Sun\Java\Deployment\
The value of the {Windows Directory} is determined by using the Win32 API GetWindowsDirectory.
So for example, on XP, the system config file is:
c:\WINDOWS\Sun\Java\Deployment\deployment.properties
The settings in this system config file will be used by all users on the system.
***************************** HIS REPLY
I've tried this and it doesn't seem to work.
I've also tried createing a deployment.config file as per the http://java.sun.com/j2se/1.5.0/docs/guide/deployment/deployment-guide/properties.html article and this doesn't work for me.
Has anyone done this successfully??
******************************** MY REPLY:
This is true.
I can get the system install to work if I add the parameter:
deployment.system.cachedir=C\:\\testcache
to the deployment.properties file found under:
C:\Documents and Settings\username\Application Data\Sun\Java\Deployment
but it will NOT work by adding it to the:
C:\WINDOWS\Sun\Java\Deployment
directory. It just creates a new default one in the user's folder.
What am I doing wrong?
If there is not a way to globally set the System Cache location, then this isn't much better than the user cache for being able to "install" the software once on the PC and let any user that signs in access that application.
We had high hopes for this, since this functionality was taken away from us once the java cache started being stored in the user's folders.
More details:
I just tried setting the mandatory=true setting and it tells me that it is not allowed to start because it can't find the
deployment.properties in the same folder (full path is displayed) but I know it is there, because it is the same folder. I even double checked the spelling.
Maybe there is a bug in the way it finds that properties file, or maybe I need to include something in that file that I didn't find in documentation?
All it has in it is the one line:
deployment.system.cachedir=C\:\\testcache
Can anybody help shed light on this?
It seems to be a bug that it can't find the deployment.properties file in the 'system' folder.
-Chris

I now found more on another thread:
http://forum.java.sun.com/thread.jspa?messageID=3500778&#3500778
You can close this one.
Sorry.

How to configure the system cache

I found that JS2E has this enhancement:
System Cache: Java Web Start now contains both system and user caches. The system administrator can now pre-load applications and shared libraries into the system cache so that multiple users can share the same resources.
Now how exactly do I pre-load applications?

Clearly the documentation of these two subjects needs to be addressed. I will try to get a compete "How to" document posted later in the month, meanwhile:
1.0)Enterprise Configuration Setup
To configure a system or enterprise configuration, you need to create a file called �deployment.config� and put it in the right place. Java Plug-in and Java Web Start will look for this file first in the directory it calls �deployment system home� , and if not found there, will look in lib directory of the JRE you are running Plug-in or Web Start from. The �deployment.system.home� directory is platform dependent. On unix, it is �/etc/.java/deployment�. On Windows it is <windows dir>/Sun/Java/Deployment.
If the file is in deployment.system.home, it will be used by all jres (only valid from 5.0 and up). If the file is not there, but in the lib directory of the jre, it will only be used when that Plugin-in or Web Start are launched from that jre.
The file contains is a java properties file, with only two possible properties in it: deployment.system.config, and deployment.system.config.mandatory. Here are two example deployment.config files:
deployment.system.config=http\://MyCompany.com/deployFiles/deployment.properties
deployment.system.config.mandatory=true
deployment.system.config=file\:/C\:/Program Files/java/jre1.5.0/lib/deployment.properties
deployment.system.config.mandatory=false
Note in both examples, the colon in a properties file must be escaped. This also applies to backslashes themselves in the examples below. This is a common problem.
The first example could be deployed by the admin in deployment.system.home, to require all jres used on this system to load the default and locked properties from the url before launching any Java Plug-in applet or Java Web Start application.
The second example could be deployed with the jre, with both deployment.config and deployment.properties
The deployment.properties file pointed to, can contain any of the properties that can be contained in the users deployment.property file (see list on http://java.sun.com/j2se/1.5.0/docs/guide/deployment/deployment-guide/properties.html). They can also lock properties by listing the property key with �.locked� appended to it. Here is an example system deployment.properties file:
deployment.user.cachedir=D\:\\deployment\\cache
deployment.security.sandbox.awtwarning=false
deployment.security.askgrantdialog.notinca=false
deployment.security.askgrantdialog.notinca.locked
The first two properties are not locked. The use can change to use a different cache location, or turn back on the AWT Warning banner. The last property is locked. The user is not allowed to grant trust to applications who's jars are selfsigned (or signed with any root not in the rootCA certificate store, nor is he allowed to change this setting. The entry in the control panel for this property will be disabled, and any change made to the users deployment.properties file for this property will be ignored.
Now for system cache:
The system cache property is:"deployment.system.cache.dir". It can be set in either an enterprise or users deployment.properties file with:
deployment.user.cachedir=D\:\\deployment\\system\\cache
/Andy

System Preferences - Sharing Panel shows after startup, why?

Systems Preferences > Sharing opens after startup but is not requested as a Login Item;
this annoys the **** out of me.
What I have tried:
     repair permissions,
     re-install mavericks
     reset permissions on Sys Pref > Sharing to no sharing
     reset permissions on "Get Info" panel
     Restart and Shut down
None of these fix the problem.
It seems to be account related; other accounts do not have that problem.
What is the simplest method to set up a new user and transfer all my data to that user and get rid of the old one?
Is there a better way to fix it without setting up a new account?
It drives me nuts.
Sigi

Hi,
I cleared the System cache using OnyX and that fixed the problem.
Thank you all,
Sigi

System cache cleaning - when is it safe, and when is not?

System cache cleaning is one of those so-called "maintenance" tasks that you may read about on the forums on Mac OS X guides that has mixed reviews, and typically is not necessary. In fact, when it is done at the wrong time, data corruption can lead to a situation where an erase and reinstall is necessary. I can't reproduce it easily, but I will say I've had it happen to at least three of my clients, so it is not as random as one would hope.
You've probably heard of browser cache, and that's safe to clean anytime you like. One thing you'll notice about when you do, is that some websites will load slower, and others will load faster depending on your internet connection, and the frequency those websites get updated.
System cache on the other hand which you'll find in ByHost and Cache folders in your Hard drive -> Library, System -> Library, Users -> yourname -> Library are a much more sensitive type of file. These will optimize the speed of frequently done operations on the operating system itself as well as specific applications which require those folders. When one of these files get corrupted, programs won't launch, will unexpectedly quit, will launch and close on their own, and in some cases Disk Utility won't function normally, or System Preference panels won't launch. To avoid these problems:
1. Only do system cache cleaning after your data is completely backed up to your satisfaction, so that a system restore won't waste your time.
2. Do it when no other applications are running, and there are no memory resident programs that may be affected by such cleaning in Apple menu -> System Preferences -> Accounts -> Login or Startup Items. Check the Process or Activity Viewer applications for applications you might have installed.
3. Do not allow the process to be interrupted until it is finished. If any power outage happens, you may be left with a corrupted cache file.
If you have a corrupted cache problem, attempt to isolate if it is happening just to one account by creating another account with Apple Menu -> System Preferences -> Accounts with admin access and see if it impacts that account as well. Do the following depending on whether or not it does affect that account:
1. If isolated to one user, go back to the user and delete that user's Library folder's cache files relating to system and Launchservices, and log out and log back in the user twice. If it disappears as a problem once, and reappears, something you are running is persistentantly corrupting that user's cache folder, and you may have to move all the non-corrupt files to the new user.
2. If it is not isolated to the user go to the System and Library folders under the hard drive and see if the Launchservices files and System cache files are removed if the issue disappears on reboot, and if it does, does it reappear after a second reboot. If it reappears after a second reboot, then you have the scary prospect of an erase and install of your system.
Don't use automatic utilities to manage your system or user cache files. If anything only manually clean the cache when it is necessary and you have corrupted files. The cache is there to speed your system, and should otherwise not be touched.

System cache cleaning is one of those so-called "maintenance" tasks that you may read about on the forums on Mac OS X guides that has mixed reviews, and typically is not necessary. In fact, when it is done at the wrong time, data corruption can lead to a situation where an erase and reinstall is necessary. I can't reproduce it easily, but I will say I've had it happen to at least three of my clients, so it is not as random as one would hope.
You've probably heard of browser cache, and that's safe to clean anytime you like. One thing you'll notice about when you do, is that some websites will load slower, and others will load faster depending on your internet connection, and the frequency those websites get updated.
System cache on the other hand which you'll find in ByHost and Cache folders in your Hard drive -> Library, System -> Library, Users -> yourname -> Library are a much more sensitive type of file. These will optimize the speed of frequently done operations on the operating system itself as well as specific applications which require those folders. When one of these files get corrupted, programs won't launch, will unexpectedly quit, will launch and close on their own, and in some cases Disk Utility won't function normally, or System Preference panels won't launch. To avoid these problems:
1. Only do system cache cleaning after your data is completely backed up to your satisfaction, so that a system restore won't waste your time.
2. Do it when no other applications are running, and there are no memory resident programs that may be affected by such cleaning in Apple menu -> System Preferences -> Accounts -> Login or Startup Items. Check the Process or Activity Viewer applications for applications you might have installed.
3. Do not allow the process to be interrupted until it is finished. If any power outage happens, you may be left with a corrupted cache file.
If you have a corrupted cache problem, attempt to isolate if it is happening just to one account by creating another account with Apple Menu -> System Preferences -> Accounts with admin access and see if it impacts that account as well. Do the following depending on whether or not it does affect that account:
1. If isolated to one user, go back to the user and delete that user's Library folder's cache files relating to system and Launchservices, and log out and log back in the user twice. If it disappears as a problem once, and reappears, something you are running is persistentantly corrupting that user's cache folder, and you may have to move all the non-corrupt files to the new user.
2. If it is not isolated to the user go to the System and Library folders under the hard drive and see if the Launchservices files and System cache files are removed if the issue disappears on reboot, and if it does, does it reappear after a second reboot. If it reappears after a second reboot, then you have the scary prospect of an erase and install of your system.
Don't use automatic utilities to manage your system or user cache files. If anything only manually clean the cache when it is necessary and you have corrupted files. The cache is there to speed your system, and should otherwise not be touched.

System Cache Issues with Windows Server 2008R2

Hi,
I'm trying to deploy Java version 1.5.0 (build 1.5.0_14-b03) on a new Windows Server 2008R2 installation. I want to use the system cache feature and have used it successfully on Windows XP workstations and Windows 2003 servers in the past. I even got it to work on a test Win Server 2008R2 server earlier this week. But on my production machine I can't get the system cache to configure.
I installed Java as usual and it installed into the Program Files(x86) directory. I copied my deployment files to the c:\windows\sun\java\deployment directory.
Deployment.config contains:
deployment.system.config=file\:/c\:/windows/sun/java/deployment/deployment.properties
Deployment.properties contains:
deployment.user.cachedir=C\:\\Program Files\\HCN
deployment.user.cachedir.locked
deployment.system.cachedir=C\:\\Program Files\\HCN
deployment.javaws.shortcut="NEVER"
deployment.javaws.autodownload="NEVER"
Not sure what's missing here especially since it worked fine the other day.
Both of these servers are virtual, VMware ESX 3.5 and were created from the same template. Only real difference is the production system will be a XenApp application server so it has XenApp installed.
Error I'm getting is that in Javaws it reports that the system cache is not configured and every time I launch my application it has to download from the source because we are deleting the local profiles when the user logs out.
Any suggestions?
Thanks in advance,
Linn

> I just wanted to know whether there will be any sort of communication or support issues between PROD and DEVE systems with such diverse configurations.
No.
You could even use HP-UX on the DEV system - as long as you're able to share a common directory to ensure transporting it's not a problem. Transports are OS and DB independent.
However, memory management and security in Windows 2008 changed significantly, you may have to use different configurations for W2K8 vs. W2K3.
Markus

Hi! I have a WD my book external hard drive plugged into my imac and I want to share it over my network with my apple tv. I went into system preferences sharing, checked "file sharing" and added my external hard drive to the shared folder. So now it is

Hi!
I have a WD my book external hard drive plugged into my imac and I want to share it over my network with my apple tv. I went into system preferences > sharing, checked "file sharing" and added my external hard drive to the shared folder. So now it is listed in "shared folders" but under "users" everything is grayed out (it says "read and write" for "everyone" - but "read and write" is grayed out, and it doesn't let me add or subtract users). Now I can access all of the folders I shared from my imac except for the externalhard drive. What's going on?

Hi RRFS!,thanks for help.I forgot to tell that hard drive has 2 partitions 1:format :Mac OS Extended (Journaled) and that works properly,2:format:MS-DOS (FAT32) and when i "get info" for both :first has shering & permitions:You can read and write - with name and privilege, second has shaing & prermissions:You can read and write- without name and privilege

Bionic Clear System Cache

When I try and clear my system cache on my Verizon bionic (Android version 4.1.2) I can get to the screen w/ the android and exclamation point but no further. If I click the volumes together I get nowhere. Is there another trick to this? Thank you.

See if this helps:
Power down phone
Hold volume up/down & power simultaneously until you see the Boot Mode Selection Menu
Use volume down to navigate to 'Recovery', use volume up to select
Should see screen with triangle and exclamation point next to an Android
Press volume up/down simultaneously to go into system recovery *
Use volume rocker to navigate to 'wipe cache' and use power button to select
Once finished, use volume rocker to navigate to 'reboot system now' and use power button to select
* if doesn't work:
press and hold the volume down and wait for a second or two, then press and hold the volume up and the volume down buttons for 5-6 seconds and then release

Empty System Cache... What Happens?

So I kinda goofed up (I think).
I was using the Application "Mainmenu" to repair permissions before installing the newest iTunes & iPhoto update. I inadvertently clicked on "Empty System Cache" instead of "Repair Permissions". Realized it about a mili-second after. I wasn't sure what that actually DOES, but afterwards a few of my desktop icons were now blank otherwise everything seemed fine.
That is UNTIL I launched Safari. I have a dual-monitor set-up and usually have Firefox running on the Left display and Safari on the Right. When I went to launch Safari, it no longer remembered where it was supposed to go & I was also UNABLE to put it there (Full-Screen on Right monitor). It doesn't seem to want to stay there anymore. It laps over to the Left monitor a bit. I try & drag it back where I like it and it just slides back. Any ideas?
Dual 2.3 G5 with 4.5GB Ram Mac OS X (10.4.9)

Hi, GregM.
Your questions are answered in Disk Utility Help, specifically:
• "Disk Utility 10.5 Help: Protecting your data against hardware failure with a mirrored RAID set."
• "Disk Utility 10.5 Help: A disk in a RAID set has failed or is missing."
FWIW and IMO, unless one is running a high-volume transaction server with a 99.999% ("Five Nines") availability requirement, RAID is overkill. For example, unless you're running a bank, a brokerage, or a major e-commerce site, you're probably spending sums of time and money with RAID that could be applied elsewhere.
For the average user, RAID is high on the "geek chic" scale, low on the practicality scale, and very high on the "complex to troubleshoot" scale when problems arise. The average user is better served by implementing a comprehensive Backup and Recovery solution and using it regularly.
Good luck!
Dr. Smoke
Author: Troubleshooting Mac® OS X
Note: The information provided in the link(s) above is freely available. However, because I own The X Lab™, a commercial Web site to which some of these links point, the Apple Discussions Terms of Use require I include the following disclosure statement with this post:
I may receive some form of compensation, financial or otherwise, from my recommendation or link.

File system cache performance

hi.
i was wondering if anyone could offer any insight into how to
assess the performance of the file system cache. I am interested
in things like hit rate (which % of pages read are coming from the
cache instead of from disk), the amount of data read from the cache
over a time span, etc.
outside of the ::memstat dcmd for mdb, i cannot seem to find a whole lot about this topic.
thanks.

sar will give you what you need....

Clean system cache and user icon

I am the admin user on my computer and everytime I clean the system cache it reverts the icon of my user to the icon of the system administrator as seen in this picture: http://image.versiontracker.com/scrnsht/48491/155862/190rootUser.png This is just a picture I found to show what the icon looks like it is not my computer as I am the only user on it.
My question is, how do I keep it from changing? Is it possible?

is there a way to re-build desktop or any de-frag utilities built in like there used to be.No. There is no re-build desktop, the closet to that would be rebuild directory and you'd need a third party app. There is also usually no need to optimize or defrag in OS X. since OS X defrags on the fly.
Have a look at Mac 101 or Switch 101 for a good start.
-mj
[email protected]

JNLP & System Cache

Hello,
I have installed a JNLP app into the system cache and it fails to run under the administrator account in Windows XP SP2. But when I install it to the administrator's user cache the JNLP app works fine. Also, if I install the JNLP app to a normal user's cache, an exception appears and it is the same as when trying to run the JNLP app in the system cache when logged in as an administrator. The exception is java.lang.NullPointerException. I should mention that I do not have the source code to the JNLP app, it is a freely available physics simulation, Phet, http://www.colorado.edu/physics/phet/web-pages/index.html. I am trying to distribute it to a school's network, so our physics teacher can utilize it in his classes.
So does anybody have any ideas why a JNLP app would not work from the system cache, even when logged in as an administrator?
Thanks

Hi, I'm having a similar kind of problem. I got the following error when I try to install the application into the system cache. I'm using command line option -system
General tab
An error occurred while launching/running the application.
Title: <title>
Vendor: <vedor>
Category: Launch File Error
Installation failed
Exception tab
JNLPException[category: Launch File Error : Exception: null : LaunchDesc:
<jnlp spec="1.0+" codebase="http://myserver:9080/installer_web/launch/" href="http://myserver:9080/installer_web/launch/installer-ext.jnlp">
<information>
    <title>Installer</title>
    <vendor>vendor</vendor>
    <homepage href=""/>
    <icon href="http://myserver:9080/installer_web/launch/images/icon.gif" kind="default"/>
    <offline-allowed/>
</information>
<security>
    <all-permissions/>
</security>
<resources>
    <j2se version="1.5+"/>
    <jar href="http://mysserver:9080/installer_web/launch/resources/app/installer.jar" download="eager" main="false"/>
</resources>
<installer-desc main-class="com.fs.launch.core.Welcome"/>
</jnlp> ]
     at com.sun.javaws.Launcher.executeInstallers(Unknown Source)
     at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
     at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
     at com.sun.javaws.Launcher.run(Unknown Source)
     at java.lang.Thread.run(Unknown Source)
But I could run the same application using user's cache. (without -system option)
I configured the system cache using deployment.config and deployment.properties files as follows.
deployment.config
deployment.system.config=file:///C:/WINDOWS/Sun/Java/Deployment/deployment.properties
deployment.system.config.mandatory=true
deployment.properties
deployment.system.cachedir=C\:\\WINDOWS\\Sun\\Java\\Deployment
deployment.javaws.shortcut=ALWAYS
JNLP file
<?xml version="1.0" encoding="utf-8"?>
     <jnlp spec="1.0+" codebase="http://myserver9080/installer_web/launch/" href="$$name">
     <information>
     <title>installer</title>
     <vendor>vendor</vendor>
     <homepage href=""/>
     <description>Version 1.0</description>
     <description kind="short">installer</description>
     <icon href="images/icon.gif"/>
               <icon kind="splash" href="images/splash.jpg"/>
               <shortcut online="true">
                    <desktop/>
                    <menu submenu="FSOnline"/>
               </shortcut>
     <offline-allowed/>
     </information>
     <security>
     <all-permissions/>
     </security>
     <resources os="Windows" arch="x86">
     <j2se version="1.5+" maximum-heap-size="250m"/>
     <jar href="resources/app/rmiserver.jar"/>
     <jar href="resources/app/common.jar"/>
     <jar href="resources/app/bsf.jar"/>
     <jar href="resources/app/xalan.jar"/>
          <jar href="resources/app/js.jar"/>
     <nativelib href="resources/app/nativelib.jar"/>
     <property name="java.rmi.server.useCodebaseOnly" value="true" />
     <extension name="Installer" href="installer-ext.jnlp"/>
     </resources>
     <application-desc main-class="com.fs.learner.core.rmi.FsdsRmiImpl">
          <argument>Main.htm</argument>
          </application-desc>
     </jnlp>
extention Installer JNLP
<?xml version="1.0" encoding="utf-8"?>
<jnlp spec="1.0+" codebase="http://myserver:9080/installer_web/launch/" href="$$name">
     <information>
     <title>Installer</title>
     <vendor>vendor</vendor>
<homepage href=""/>
     <icon href="images/icon.gif"/>
     <offline-allowed/>
     </information>
     <security>
     <all-permissions/>
     </security>
     <resources os="Windows" arch="x86">
          <j2se version="1.5+"/>
          <jar href="resources/app/installer.jar"/>
     </resources>
     <installer-desc main-class="com.fs.launch.core.Welcome">
     <installer-desc/>
</jnlp>
Please help. thx

System cache on CITRIX

Has anyone out there got the system cache working on a citrix server. Have set it up on xp boxes with no issues but on Citrix it just will not recognise that the system cache has been configured

It is supposed to do this. Windows can be very aggressive in caching data and code. This data is released as soon as the system needs memory for something else, but when it is unused, the system uses it to cache all sorts of stuff. It utilizes the memory
which would otherwise be unused. Leaving it unused would basically be a waste.
So in other words, nothing is wrong. It is windows which decides to try and be more efficient. As soon as a request for more memory comes in, it just drops whatever is needed from the cache immediately.
This is one of the reasons that in later versions, the memory is reported differently in task manager, because people kept trying to stop the system from caching because they wanted to see more 'free' memory.

The Problem about clearing the system cache

Hi, there!
I'm trying to draw a lot of image in iPhone programming.
I used [UIImage imageNamed].
but it doesn't clear immediately the system cache.
At last it occurs the out of memory.
So I thought using imageWithContentsOfFile, but it works very slowly.
Does anybody know how to clear the system cache?

Read Position.flx can execute much faster than 5 ms but as it reads a register that is updated every 5 ms on the board, it reads the same value multiple times.
To get around this problem there are two methods:
Buffered High-Speed-Capturing (HSC)
With buffered HSC the board stores a position value in it's onboard buffer each time a trigger occurrs on the axis' trigger input. HSC allows a trigger rate of about 2 kHz. That means, you can store a position value every 500 µs. Please refer to the HSC examples. You may have to look into the buffered breakpoint examples to learn how to use a buffer, as there doesn't seem to be a buffered HSC example available. Please note that you need an external trigger-signal (e. g. from a counter of a DAQ board). Please note that the amount of position data that you can acquire in a single shot is limited to about 16.000 values.
Buffered position measurement with additional plugin-board
If you don't have a device that allows you to generate a repetitive trigger signal as required in method 1.), you will have to use an additional board, e. g. a PCI-6601. This board provides four counter/timers. You could either use this board to generate the trigger signal or you could use it to do the position capturing itself. A PCI-6601 (or an M-Series board) provides can run a buffered position acquisition with a rate of several hundred kHz and with virtually no limitation to the amount of data to be stored. You could even route the encoder signals from your 7350 to the PCI-6601 by using an internal RTSI cable (no external wiring required).
I hope this helps,
Jochen Klier
National Instruments

JWS system cache (shared!?!)

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